blackbox

A LÖVE library for recording and playing back LÖVE events.

Usage

An example usage that will initialize blackbox when the project loads and after 30 seconds replay all love events it receives.

local blackbox = require("blackbox")

-- total time elapsed
local gt = 0

function love.load()
	-- your loading code here
	
	-- initialize blackbox
	blackbox.init(true)
	blackbox.startRecord()
end

function love.update(dt)
	-- update global time
	gt = gt + dt
	
	if gt >= 30 and blackbox.state ~= 'playback' then
		blackbox.stopRecord()
		blackbox.startPlayBack()
	end
	
	blackbox.update(dt)
end

API

blackbox.init(popLast*)

• popLast bool If true, it will remove the very last signal received before being told to stop recording. This prevents getting stuck in a loop if you have any of blackbox's controls bound to buttons. Initializes blackbox with a start time. This creates a reference point in time to the beginning of a playback session. If this isn't done at a consistent point in time (like loading a menu) then recordings may not be accurate.

blackbox.update(dt)

• dt int The time elapsed, provided by love.update(dt). Update the internal time step for playing back events. This is only necessary for playback, as events automatically capture the time they were received.

blackbox.startRecord()

Wraps all the default love event handlers and begins recording all events to a buffer. This will do nothing unless blackbox is idle (not recording or playing back).

blackbox.stopRecord()

Unwraps all the event handlers to their original state before the recording began. If at any point the love event handlers were modified after the recording began then the game may not return to standard behavior. This will do nothing unless blackbox is idle (not recording or playing back).

blackbox.startPlayBack()

Begin playing back the contents of the event buffer using the instant this is invoked as the same instant startRecord was invoked relative to blackbox.init(). This will do nothing unless blackbox is idle (not recording or playing back). Requires blackbox.update() to be called in order to step through time.

blackbox.stopPlayBack()

End playing back of the event buffer. Does not rewind the internal time or playlist location. This will only do something if blackbox is playing back.

Notes

• If your code or any libraries you use rely on love.keyboard.isDown() then this will not produce accurate replays, as they do not respond to keypress events.
• Love doesn't provide a precise way of scheduling events, so desyncs can happen if your game doesn't use a fixed timestep.